Autonomous vehicles, such as vehicles that do not require a human driver, can be used to aid in the transport of passengers or items from one location to another. Such vehicles may operate in a fully autonomous mode where passengers may provide some initial input, such as a destination, and the vehicle maneuvers itself to that destination.
A key component of an autonomous vehicle is the perception system, which allows the vehicle to perceive and interpret its surroundings during a trip. When the autonomous system is engaged, the system will make various decisions during the trip, for example, speed up, slow down, stop, etc. The operator may be unaware of the calculations or “reasoning” behind why the autonomous vehicle is taking some particular action. In order to feel safe and confident, the operator may want to know what the vehicle is planning to do in the immediate future.